1. Field of the Invention
The present invention relates to a flash apparatus, and a camera having a flash apparatus.
2. Description of the Related Art
There have been various proposals relating to techniques for reducing the temperature rise of a light emission section and a charging circuit, attributed to continuous light emission of a flash apparatus.
For example, Japanese Patent Application Laid-Open (JP-A) No. 2001-228511 discusses a construction configured to operate a light emission preventing section (which reduces light emission), during a continuous and full light emission mode, in order to cope with an associated temperature rise. The construction also prohibits the light emission preventing section from operating during a light amount control mode.
Also, JP-A No. 2001-242510 discusses a construction configured to count the number of times of light emission within a predetermined period of time and limiting charging operations based on the counting results.
Further, JP-A No. 10-170994 discusses a construction configured to actually detect the temperature inside a flash apparatus so as to limit the temperature rise.
However, the construction disclosed in the JP-A No. 2001-228511 can only roughly reduce the temperature rise, because, even in the case where the amount of light emission is controlled, the temperature may rise to a great extent, or conversely, if the light emission is reduced to a certain level, the prevention of the light emission may not be required.
In JP-A No. 2001-242510, the number of times of light emission is counted, and it assumes that there is full light emission. While the light emission amount varies in accordance with light amount control, a change of a calorific value due to a light emission is not considered in the light amount control and only roughly is a temperature rise detected. Conventionally, a light amount controlling system is mainstream in the flash apparatus market and a digital camera can be used in continuous shooting more often than a film camera due to its low running cost. Therefore, the digital camera is required to continuously shoot images while reducing an operational temperature rise. An increased efficiency of operation would be facilitated by finer control and reduction of associated operational temperature rises.
Further, in JP-A No. 10-170994, a detecting section for detecting the temperature inside the flash apparatus is included in the described device, which could give rise to increased manufacturing costs and detecting section arrangement issues.